"usual, typical, or Expected".........--Longman Dictionary of American English

Kind of a weak definition. "according with, constituting, or not deviating from a norm, rule, or principle b : conforming to a type, standard, or regular pattern" http://www.m-w.com/cgi-bin/dictionary[/img]

"Take four red capsules, in ten minutes take two more. Help is on the way."
----- Voice from the Medicine Cabinet

Because homosexuality is a choise. And humans have the right to a choice(No, i am not a homosexual ) There are a lot of human right organisation that fight for the right of homosexual individuals, so, as James said, education is a much better target

"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

Homosexuality may have some genetic basis and also, an essential environmental cause. I've seen a doc.film on discovery on homosexual-animals [ i mean not humans].
There are many animals in African grasslands that show homosexuality , there might be any sexual abuse here, but the possibility of hormonal changes and other sexually affecting changes due to environmental as well as genetic factors [ getting some genes on or off etc] which would result in the abnormality in the developement of brain.
This may happen even in the fetal stage . But not completely , of course.

AN EXAMPLE OF PLANNED HOMOSEXUALITY[ from the doc. film].-There are male ducks that are homosexual and their duck partners are bisexuals. And these homosexual-ducks help them grow their offsprings better there by increasing the chances of survival of the progeny.!!!

This appears to be planned homosexuality and in comparison with poppulation without homosexual ducks , this poppulation has some selective advantages , from natural selection pt. of view.
For humans, the need to lessen the reproduction rate , such things may occur. But as in that poppulation of ducks male-homosexuality was considerably dominant over female homosexuality that change the reproduction rates t o a lesser extent than if the % of male and female homosexual were to be same [ ducks don't expect the reduction of reproduction] .

I don't know about hearing voices, but under certain stress conditions monkeys can go very odd. there were a bunch of pretty cruel behavioural experiments done by Margaret and Harry Harlow into social deprivation in rhesus monkeys. they took baby monkeys away from their mothers and all other monkeys and gave them a 'surrogate' mother, usually made out of chicken wire with some sacking wrapped round it. these baby monkeys went fairly crazy, sitting in the corners of their cages, rocking backwards and forwards, even biting themselves. sounds crazy to me!

btw these weren't recent experiments, they were done quite a long time ago, when people didn't care very much about the monkeys.